upgrade k8s api to v0.20.6

Author: sleshchenko

go.mod

@@ -4,16 +4,16 @@ go 1.13
 
 require (
 	github.com/ghodss/yaml v1.0.0
-	github.com/google/go-cmp v0.4.0
+	github.com/google/go-cmp v0.5.2
 	github.com/google/gofuzz v1.2.0
 	github.com/hashicorp/go-multierror v1.1.0
 	github.com/lucasjones/reggen v0.0.0-20200904144131-37ba4fa293bb
 	github.com/mitchellh/reflectwalk v1.0.1
 	github.com/santhosh-tekuri/jsonschema v1.2.4
-	github.com/stretchr/testify v1.4.0
-	k8s.io/api v0.18.6
-	k8s.io/apiextensions-apiserver v0.18.6
-	k8s.io/apimachinery v0.18.6
+	github.com/stretchr/testify v1.6.1
+	k8s.io/api v0.20.6
+	k8s.io/apiextensions-apiserver v0.20.6
+	k8s.io/apimachinery v0.20.6
 	sigs.k8s.io/controller-runtime v0.6.3
 	sigs.k8s.io/yaml v1.2.0
 )